Before you embark on a makeover for your living room, beware: certain styles of home decoration could damage your health.

Research published in the journal Nature shows that indoor pollution is considerably higher in Northern than in Southern Europe. Scientists believe the different styles of home furnishing favoured across the continent may be to blame.

In particular, they point the finger at the stripped pine, linoleum and carpets, which are common in northern homes.

It is possible that these materials are better at trapping and absorbing polluting chemicals than the tiles, marble and white-washed walls, that are the fashion in Greek, Spanish and Italian houses.

Dr Vincenzo Cocheo, of the Fondazione Salvatore Maugeri-IRCSS, Italy, and colleagues, tracked the movement of traffic fumes into the home.

Incomplete combustion

They were interested in what happened to benzene, a well-known carcinogen, which is emitted by vehicle engines when petrol is not completely burnt.

The scientists compared the benzene exposure of 50 people in six cities in Belgium, Greece, Denmark, Spain, Italy and France.

The team discovered that indoor pollution was worse in Antwerp, Rouen, and Copenhagen than it was in Padua, Murcia, and Athens.

The results revealed that in a typical day people encountered twice as much benzene indoors as roadside measurements would indicate.

"The pollution indoors is generally higher than outdoors, possibly because of an imbalance between the flow of pollutant from outside and its removal from inside to outside," the researchers say.

"In other words, the house itself could be acting as a flypaper created by absorbent surfaces on walls, floors and furnishings.

"This idea is supported by the lower indoor pollution in southern European towns: in northern European houses, carpets, linoleum and wood surfaces are favoured, whereas tiling, marble and bare walls are typically used in southern Europe."

Leukaemia risk

Benzene is suspected as a cause for leukaemia. Its risk has been estimated in previous research at four cases per million among people who experience lifelong exposure to concentrations of one microgram of benzene per cubic metre of air.

The study found that in Murcia, Spain, people were exposed to up to 23.1 micrograms per cubic metre. However, this figure was not a constant as it varied according to traffic levels, proximity to the street and lifestyle.

In addition, the researchers warned: "Personal exposure, and therefore risk estimates, cannot simply be estimated from environmental concentrations of benzene."

Dr Cocheo told the BBC that letting fresh air into homes during the night when urban pollution is at its lowest, was the best way to reduce indoor pollution, making your house a cleaner and safer place.